Tom - Falsing tones - One more time on this subject please

Hunting in nail infested sites I am dealing with a lot of falsing. Its slow going because I am spending a lot of time investigating the many iron nail falses I am encountering. I started a thread on this subject a while back, but would appreciate a followup on one thing.

Tom you stated the following in the previous thread:

Yes, nails will 'false' to other tones other than the correct low-tone. Usually......in general.....the iron false is a high-tone. You MUST go through a learning curve as to which signals are a iron 'false'......and which are a good non-ferrous audio hit in between/amongst iron targets. It is quite difficult to explain (using words only) as to 'preamble' and 'postamble' (the key to which determines "success"winking smiley audio 'sharpness' whilst detecting iron infested sites.

I know you said it is difficult to put in words but would you please describe as best you can what you are listening for in terms of the preamble and postamble? Would it be a valuable learning exercise to drop a good target on the ground and compare it to a falsing signal the next time I think I have encountered a falsing signal in the field?

Thanks

I am not the right "Tom" but could not resist an answer to your question. So here goes:

Some objects will give a false high signal. But with practice you will be able to hear and see the difference. In all metal mode when searching, when I receive a signal that is not a good clear, sharp signal, I will circle around the target. 360 degrees around the target. Often a false signal will onle be present 30 to 50 percent of the time when circling the target. Another way to identify a false signal is by the sound.
The signal will be a higher tone but will be in Tom's words WASHED OUT. This is a raspy of fuzzy tone. A good target will often produce a nice sharp tone. If you are have knowleged of sine waves, visualize the sine wave in your mine of the signals that you hear. If the signal has a quick or sharp increase and decrease in amplitude of the sine wave then in is most likely a good target. If the target has a fuzzy , slow increase and decrease of the wave, then it most of the time will be a false signal. I use this also on the metal screw tops of beer and soft drinks. These will give a quarter signal but will almost always
have the fuzzy or washed out sound. With practice you will soon get where you will not have to even look at the detectors indicators to determine a targets validity.

Other options:
Use a smaller coil, this will decrease depth just a small amount but will allow you to work around a good portion of the trash.
Use a small amount of discrimination. The magic number on my detector is 16, this seems to remove all the small iron objects with no decrease in depth.

Good luck
T

Tom, I hope I did not give any incorrect info..........

The best way I can explain it is actually preltty simple, when you are in an area with lots of iron falses instead of checking out each and every signal keep sweeping until you hear something different in the tone. Those are the ones to check out! They can be the softer hits of a deep target, a short sounding quick beep (ie: 'coin sized') or just something that can't easily be explained as Tom D noted. Don't worry about missing targets during this mental training period, use it as tool to train the brain the difference between the 'white noise' of falsing which in some conditions is the VAST majority of signals and the good signal worth investigating.

That said some conditions/detector settings simply do not allow for this. For instance the T2 at disc 21 Pf process has no tonal variation to pick up on, thus other than upping the disc to 22, resweeping each and every good tone to see if it will repeat is an absolute neccessity and the primary reason most prefer the 2 tone mode even tho it may miss a few good targets.

And, do not forget that in iron infested areas to use slow well controlled smooth sweeps. Detector circuits do NOT like changes in sweep speed or coil height in iron infested sites. After hunting less trashy areas I find that I sometimes have to mentally re-adjust to 'iron mode' and be more careful with my sweep techinique.

Tom Z

In a nutshell with experience for the most part audio variances will let you know right from the get go what signals to follow up on and which ones to leave lie..Indeed not always the case but generally it will cut down your odds after you use a unit for some time...

In addendum an educated ear comes with time and one beep does not always sound like another beep but we all get fooled now and then just not as often...

But falsing is just that...I have hunted place where that happens and I think the LTD is not fast enough to tell it is iron so it give me a high tone bu won't repeat.....If it does repeat it can still be a nail but on my last hunt the nails had relics mixed in. So you just never know. I never just dig the perfect tone. I found a 1857 seated Liberty at 8 inches that gave a dirty tone that bounced and was hard to locate. I slowed down and looked at the ground and found the area that I hoped the target would be. Thinking it would be a half rusty nail I dug 8 inches to find a perfect sivler coin....What a rush

LowBoy

TAKE A LITTLE TIME KICKBACK AND WATCH SOME OF MY DETECTING VIDEO'S BELOW ON YouTube

[www.youtube.com]

If you don’t dig it, then how are you going to know what you’re missing!
How can you have your pudding if you don’t eat your meat!

Thanks to all you guys. You've given me some good pointers.

One question though. I'm using an F75 LTD. I seem to recall that Tom D. said the tones in the LTD are electronically produced as a "catch your attention" signal and aren't directly derived from the raw signal data. I guess that would mean that the LTD's tones may not vary in quality in a way that would be useful in determining a good target from a bad one. Am I mistaken on this?

I went out awhile ago and got one of my rusty nails to do some testing. I got in the right geometry to bring in a nice 2 way high tone false off the end of the nail. It sure sounded sweet. I then placed a clad dime down and I definitely can't tell the difference in the two with my F75 LTD. Both are sharp, crisp, and clean. Tom's suggestion to watch the Confidence bar is on the money though. Only 1 bar on the nail false. Also raising the coil even slightly causes the nail false to break up. Of course the dime hangs in there as you raise the coil. I also tried AM as you guys suggested. Just as you said, you can discern the false by the low amplitude signal at the location of the false and the change to a solid iron hit as you move away from the false location toward the nail.

I must say though that I can discern no difference in the tone of the iron nail false and the clad dime in discriminate mode. Both sound extremely good. I think its got something to do with how the F75 LTD generates tones as I stated above.



Edited 1 time(s). Last edit at 05/18/2010 02:00AM by dgc.

Well in the ground it can change what you hear the LTD gives you alot of info but sometimes a nail and a target can sound sweet and sometimes you can hear both of the targets. If you relic hunt alot you will find times when all goes well and when the iron gives you a sweet tone.

LowBoy

TAKE A LITTLE TIME KICKBACK AND WATCH SOME OF MY DETECTING VIDEO'S BELOW ON YouTube

[www.youtube.com]

If you don’t dig it, then how are you going to know what you’re missing!
How can you have your pudding if you don’t eat your meat!

These are all good answers. And it seems like you are answering your own question. Multiple inputs on one 'questionable' target will help determine; dig/no-dig.

1. Upon initial lock-on to a target.....find where it sounds at its best (fore-to-aft). This will be from 'X' direction.
2. Then rotate your body around this 'best sounding' spot and find out where it sounds at its best whilst changing angle-of-attack direction via body rotation. You will now have the best X and Y pinnacle.
3. Glance at the Conf. bargraph.
4. You could raise the coil ..... and lower the coil....for yet another data input.
5. When the coil is being swept at the best possible approach.......how 'sharp' (or washed out) does the target sound.

All of these inputs will help you make the decision; dig/no-dig. This sounds like some technical/difficult stuff.......but.......in time, you will be doing this in near instant/rapid succession and not know it. It'll become 2nd nature. There are a few other things you can do........but I do not want excessive difficulty to ensue.

Thanks Tom.
Did you see what I said about how the F75 LTD generates tones? If I remember correctly, tone generation is not based on raw data. Would that not make it more difficult to discern good from bad based on omly how the tones sound?

There are multiple things that create the 'artificial intelligence' tone data.......starting with the base/raw data. Yes, just being reliant upon only the tones could handicap performance results. This is why.......in some circumstances.......monotone is more preferred. High iron infested sites with a lot of falsing among the tones may force you to use monotone......and have much better results, less fatigue and smoother responses. Once you decide to stop on a target and do further investigating.......you can then watch the VDI numbers....to help aid you in 'target conductivity averaging'......assuming you are still in monotone.